Sample Collection Procedure for Calibration and Validation

Most companies outline sample collection procedures in a Best Practices write up.  Consistency in sample collection and sample processing is the most important variable for good sample analysis. 

Samples should be collected and immediately taken to the laboratory or packaged for shipment to an outside lab in a sealed moisture barrier container or bag.  If sending samples to an outside lab an additional moisture barrier tape should be applied around container lid.  If samples are delivered to an in-house lab the procedure must outline for lab personnel the time to grind or process sample prior to measurement.

Calibration samples should be done individually meaning that sample one is ground, weighed, placed in oven for specified time interval at specified temperature for that product and weighed again for moisture determination.  At that point the next sample is processed.  Grinding all samples initially introduces an opportunity for increased variation while they await analysis unless all samples can be placed in the same oven immediately.

Consistency is the key to this process.  If the first shift collects samples and the lab analyzes these samples when received, results are good.  If another shift or operator collects the samples in a different manner or lets them sit for a while before bringing to the lab, or the lab lets samples accumulate before processing, variations can occur.  Consistency is important for successful calibration.

Alternatively, samples can be created in the lab and allowed to equilibrate.  These samples can be used for calibration.  A final double- blind target set point sample should be analyzed and averaged to determine any offset (zero) adjustment on-line.

Other parameters such as fat and oil are subject to stratification and a well-mixed double-blind sample analysis is even more important for these constituents during calibration.

 

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PSTC – PSC Poster Calibration Techniques Featured

Pressure Sensitive Tape Council Meeting Orlando Florida 

A Sticky Affair!

 

Pressure Sensitive Tape Council is a highly technical conference featuring world class presentations on current and emerging technologies that benefit the tape manufacturing process.  PSTC also has a very collegial feel with technical people who know situations change and friendships remain.  Our Near Infrared Calibration Procedures Poster was featured in the afternoon session.

We appreciate and thank you for our time together at PSTC May 2016!

 

PSTC May 2016 Table Top

 

 

PSTC w Customers at Table Top May 2016         PSTC Poster Board Calibration Sampling May 2016

Powder & Bulk Solids Show Chicago A Flaky Affair!

Powder & Bulk Solids Show in Chicago was a success!  First day was a bit slow but second day was high traffic and lots of contact with existing customers with new projects and new customers seeking solutions to their moisture problems.

Interestingly, many of the new inquiries were for Flake Applications which are easy applications for our Near Infrared Technology.  Also much interest in our Snorkel Sampler for hopper, vertical and gravity conveyor applications.

Jun and Lucia presented our products and enjoyed the Windy City!

 

Powder and Bulk Show Jun Lucia May 2016

 

 

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What is a Double-Blind Sample and Why Do I Care?

Double-blind refers to the same collected sample being divided into two samples and analyzed “blind” meaning that lab technician or off site lab does not know that within the samples being analyzed that several are duplicate samples.

When calibrating an analyzer the results can never exceed the laboratory accuracy and sample collection method.  Variances can be due to sample collection, head space in sample container, temperature and duration and type of lab method and other variables.  All can be minimized in a simple specific procedure outline for the product.

Moisture samples should be collected in a polypropylene or other suitable container with a moisture barrier lid.  Container should be full with minimal air head space.  Crush samples if possible to increase sample density.

Determine the appropriate sample size 200 – 450g, temperature and duration for weigh dry weigh lab determination of control samples.  Many labs feature automated weigh dry weigh analyzers that predict sample moisture.  The higher the temperature of the convection oven the quicker the extrapolate result, and usually a less accurate result.  While this speeds sample turn around and increases throughput its contribution to variance must be considered.  Hence, double-blind sample averaging minimizes this variation and improve calibration.

For example, using a weigh-dry-weigh gravimetric procedure with an oven temperature of 115?C for 6 minutes will yield a different result than running the sample at 80?C two or three hours.  There also may appear to be “crisping” or “sample browning” at the higher temperature that adversely impacts accuracy.  Again, this is in regards to calibration samples and not necessarily day to day production lab tests that require rapid turn around and high throughput.

Let’s view results for samples tested at 80?C, 115?C and those sent to an outside sample as double-blinds.  Outside labs can be subject to the same variation as in-house labs and double-blind samples reveal the accuracy of their results too.  The chart below shows the benefit of using double-blind samples for calibration and any subsequent validation to improve accuracy.

 

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PSC Seeks to Expand Representation in South and Central America

Process Sensors is seeking to expand representation and service of our product line in some parts of Central and South America.  Our areas of interest are outlined below.  Process Sensors offers a complete line of Near IR and RF gauges for industrial manufacturers who need to measure moisture, oil/fat, additives, Cross Direction Web Profiles and other systems.  Systems are for process, at-line and lab applications.

Costa Rica y Nicaragua:  We are interested in representation, preferably with an office in centrally located San Jose, Costa Rica.

Panama:  We seek representation with a company that has demonstrated success in process industries.

Ecuador:  We seek representation with an industrial manufacturer’s rep, preferably based in Quito.

Venezuela:  We seek representation for applications that have sufficient Return on Investment to attract consideration for both domestic and multi-national companies seeking to grow market share.

 

Please contact us at info@processsensors.com

Gracias!

South and Central America Map Seeking Rep Blog 042116

Happy Friday!

Happy Friday 032516

Happy St. Patty’s Day!

St. Patty Leprechaun kid 031716St. Patty’s Day is celebrated on March 17th to honor his death in 461 A.D.   Allegedly he was born in 385 A.D. to Roman parents in Wales and kidnapped at the age of 16 to be sold into slavery in Ireland.  There, while working as a shepherd he had a religious experience and began preaching. 

33.7 Million Americans of Irish Descent, about 7 times more than the population of the Republic of Ireland (4.6 Million)

First St. Patty’s Day Parade was not held in Ireland.  It was held in Boston in 1737 and NY began the tradition in 1762.  The parades were held to demonstrate the growing social and political power of the often oppressed Irish immigrants

Guinness sells 5.7 Million pints per day on average.  Sales jump to over 11 Million pints on St. Patty’s Day

First US President to attend a St. Patty’s Day Parade was Harry Truman in 1948

Largest St. Patty’s Day Parade is in New York City drawing over 1 Million people.   In Chicago, Illinois they dye the river with 40 tons of Kelly Green eco-friendly vegetable dye.  The tradition started in 1962.  The color lasts for between 5 and 8 hours.  Catfish must love it!  Among the largest celebrations are Boston MA (since 1901) and …… Savannah, Georgia!

Shortest St. Patrick’s Day parade is in Hot Springs, Arkansas at 98 feet

The original color associated with St. Patty’s Day was blue, it later became green associated with the green springs in Ireland and allegedly a freedom movement.  You will often see blue as an alternate color to green among revelers

The Shamrock is associated with St. Patrick as he used it as a metaphor for the Holy Trinity when he introduced Christianity to the Pagan Celts

While legend has it that St. Patrick drove the snakes from Ireland, there are actually no snakes native to Ireland.  It was too cold in the Ice Age for snakes to survive and the surrounding ocean prevented any snakes from reaching Ireland

The traditional Irish meal of Corned Beef and Cabbage has nothing to do with corn.  The “corn” refers to the large salt crystals used to cure the beef

“Erin go Bragh” roughly translates to “Ireland Forever”

 

St. Patty Day Chicago River Green 2 031716St. Patty Day Parade 031716St Patty Day happy-leprechaun-28818778

 

Process Sensors Corporation Service Contracts

Service Contracts Protect Your Capital Investment.  Two visits per year to certify correct operation and calibration, provide training for new operators, optimize any communications and answer questions.  The Service Contract includes a discount on any replacement parts out of warranty. 

 

Mikhael and buds in construction hats 062515

 

The services provided include:

Preventative Maintenance:

  • A complete diagnostic check of voltages, internal temperature, detector signal, gain, optical filters measurements and optical balancing. All necessary adjustments will be performed. Should any replacement parts be required, they will be supplied during the visit at a 15% discount.
  • Minimum of two Service and Maintenance visits per year. 
  • Remote Diagnostics via Internet as needed.  

 

Calibration:

  • All MCT Gauge calibrations will be confirmed using the customer’s current lab methods.  An adjustment to the calibration or full calibration of each MCT Gauge will be performed as required.

 

PLC and Computer Program Check:

  • For MCT Gauges and Frames connected to a PLC or PC, the diagnostics and communications will be checked to ensure that the MCT Gauges and Frames are performing and communicating properly.

 

Training:

  • Operator, Maintenance and Quality Assurance Technician training can be provided during the service visit. The training would be for the operation, calibration, maintenance and repair of the MCT Gauges. The training may cover:
  • Near-Infrared Theory
  • MCT Gauge Operation
  • Changing Product Codes
  • Confirming Calibrations
  • Performing Off-set adjustments to the Calibration
  • Performing a Full Calibration
  • Preventive Maintenance and adjustments
  • Repair and replacement of parts

Additional Training can also be provided to meet specific requirements of your facility. 

Let’s Discuss Today!

So, You’ve Decided that a Photometer will Meet Your NIR Application Needs

Why Choose Process Sensors?

 

Photometer Illustration 120313

Superior Technology & Support After Sale At A Reasonable Price

 

  • Accurate & Reliable
  • Easy to Operate &  Easy to Calibrate
  • Dual Core Architecture:  One core dedicated to NIR signal acquisition and the other programmed to manage computations and communications options
  • Built in cooling panel and air purge assembly
  • Adjustable filter wheel speed
  • Embedded bootloader for firmware upgrades
  • Viewer Suite Software:  Allows remote viewing  and editing of all MCT Transmitter functions
  • Communication Options:  Ethernet, Ethernet IP, OPC, Modbus TCP, Devicenet, Profibus etc.
  • Support After Sale:  Two Year Extended Warranty on Parts and Labor
  • Remote Trouble Shooting & Diagnostics

Free Sample Analysis, Feasibility Studies & On-Site Demo

Call Us Today to Discuss Your Application!

Photometer or Spectrophotometer for Your Application?

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Best NIR Product Differentiation is Based On Application, Price, and

Ease of Use Considerations

 

Photometers are both well suited and established for the measurement of moisture, oil/fat and other easy to identify applications.  Photometers typically use targeted measure wavelengths where the parameter absorbs such as 1.94 microns for water and 1.72 microns for oil.  The Photometer then compares the response with non-absorbing wavelengths.  Sugar sprays can be measured based on the water carrier and flavorings based on the oil.  Photometers are typically the best choice for these types of applications.

Spectrophotometers measure the full spectrum and then use slices of that spectrum, not the whole spectrum, to generate factors via chemometrics or mathematical modeling such as PCR, PLS, Neural Networks and other treatments.  When the parameters being measured have overlapping absorption bonds such as different types of alcohols or saturated and unsaturated fats, they can discriminate between the constituents.    Also, for more difficult applications such as protein, salt, sugar, ash etc. spectrophotometers have advantages over photometers.

Calibrations for Photometers typically need 3 to 7 samples throughout the range of interest.  Calibrations for Spectrophotometers typically need 10 to 15 samples per modeling factor and can require as many as 200 or more samples to calibrate.

Photometers are significantly less expensive, easier to calibrate and easier for unskilled workers to operate.  If a Photometer meets your measurement needs, it’s a better choice for on-line, at-line and lab measurements.